Molding apparatus



Aug. 23, 19,32. v T. ROBINSON MOLDING APPARATUS original Filed July lo, 1928 Patented ug. 23, 1932 UNITED STATES PATENT oiFFicE f THOMAS ROBINSON, ORNEW YORK, N. Y., AssiGNoR rro 'LANCASTER ASPHALT', INc., or NRW YORK, N.v Y., A CORPORATION or DELAWARE y f MOLDING APPARATUS Original application iiled July 10, 1928, Serial No. 291,638. Dividedami this application filed November 23,

, 1929. Serial. No. 409,302. Y

Thisinvention relates to molding apparae tus and is concerned more particularly with molding drums of novel construction which is particularly adapted for the production of rooling elements of the type set forth'and described in my Patent No. 1,698,242, issued January 8, 1929. The apparatus ofthis invention 'is also useful in the production of roofing elements of the type set forth and 13 described in my co-pending application, Sleriai No. 291,638, filed July 10, 1928, of whichv the present application is a division.

accordance with the method disclosed in the 15 patent, a plastic material capable of hardening is placed between a pair of jacket sheets4 and the plastic mass jacketed by the sheets is passed between a pair of molding drums having cooperating moldingcavities in the faces thereof. The drums exert pressure `on the sheets and plastic material and givesef' lected portions of the jacketed mass the,

shape of the final roofing products which is determined by the shape of the moldingl cavities. These cavities are provided with knife edges by which the sheets are cut or scored along the outlines of the formed units. j

According to the process disclosed in my co-pending application, the material acted:

on 1s a composite web made up of plastic material and fibrous material mixed therewith. VThis sheet, which is of uniform thickness, is introduced between a pair of molding 5 drums with cooperating cavities therein of appropriate shape and the drums exert pres- A sure on the web and form selected portions:

thereof into nal roong products.

The present invention is concerned with a molding drum for the purpose above deedges defining the mold cavities. The boti forms. In the manufacture of roofing elements in Y such that `the units can tomsl of the cavitiesare defined `by mold plates removably secured in position and supported from beneath by a cushion material p plates determine the shape ofthe final prod- Y uct and these plates can bereadily removed from and replaced on the drum, it is apparent that a pair of drums may be 'used for the production of products 'of many different For a better understanding of the invention, reference may be had to the accompanying drawing, in which Fig. lis a sectionaljview diagrammatically illustrating the operation ofthe molding apparatus;

Fig. 2 is a` transverse sectionof a single drum of the invention; and o Fig. 3 is a face view of a portion of such a drum. y l i The drums illustrated are appropriate for the formation of'single shingles which have a. tapering thickness from one end to the other. Each drum consists of a hollow cylinder 10 which is provided with a pluralityof proj ecting knife edges l1v on its, periphery. These knife edges are preferably of triangular section and maybe formed as'l an integral` part ofthe drum itself. The knife-edges define the cavities by which the roofing elements are given their final shape and form and the knife edges cooperate to sever' the blank which is fed to them along the outlines of the elements or else score-the blank to a depth be readily removed from it. Y

In the drum illustrated in Fig. 3, there are circumferential knife edges 11m and axial knife edges 11b. Preferably there are aplura-lity of circumferential knife edges so that the drums may act on a sheet'of a width equal tothe width of a plurality ofshingles, and thus form a number ofV shingles at one operation. The axial knife edges 11b extend between adjacent circumferential knife edges y 11a. v i y Each mold cavity defined by parts of knife edges 11a and 11b has a bottom defined by a mold plate 12 held in place by bolts 13 which pass through the plates and into threaded openings in the drum Wall. These plates have a shape which determines the thickness and shape of the final product. The form illustrated is constructed for the forma- Y tion of tapered shingles such as that shown at 14, and accordingly each plate 12 has a thin end and a. thick end, so that when the blanki's passed between aY pair of drums, the sheet' is reduced in"thickness between the thick ends of plates 12, one on each drum', and Vthe thickness of the blank is increased in the space between the thin ends 'of plates 12, 'one on each drum. y Y

The blank employed may ltake various forms, as lfor example, it may be in .the form of a'single sheet of plastic material of substantial thickness or of apai-r of thin sheets with `plastic material between them. The

f blank is delivered to the drums with the plastic ingredients thereof suciently fluent to permit the drums to vary the thickness in the manner described. A

rIlhe plates 12 which determine the shape of the final product may be readily removed and replaced byothers of a different contour so that final products of dierent kinds may be readily produced. For this 'purpose the bolts 13 are unscrewed and other plates, approf f priate for thepurpose, substituted for them.

` wall.

Beneathy the plates, there is a cushioning layer 15 which lies between each plate and the face ofthe drum. The cushioning` layer is preferably of metal andimay be Zinc, lead,

or the like. `This cushioning'material is pref-v erably placed in positionafter the plates 12. have been mounted in the cavities and for this purpose, Vthe metal in molten form is introduced through openings 16, through the drum When the met-al solidifiesthe mold plates 12 are supported from beneath by a solid metallic'layer whichinsures thatthe plate is supported evenly throughout its surface and is thus'relieved ',of'strains :which Vifmight arise from improper setting.

are discharged thin end first.

AThe drums are intended to rotate in the direction indicated by the arrows inl Fig. 1 so that as the blank 17 passes between the drums, thethin ends of the elements are first formed and the actonof the molding cavities of the drums causes thefmore fluent portions of the blank to be displaced rearwardly' with respect to the direction of movement of the blank through the-drums, so that the products drums operate in this manner, proper displacement of the blank material is insured and the space defined by a pair of cooperating cavities, one on each drum, is completely lled by blank material so that perfect products `are produced.

' The drum illustrated is constructed for the production of individual roofing elements of generally rectangular shape-but it willbe voutlines of vthe individual products.

When the y druinsro't'ate-and serve either tosever the.n

blank material or'elseto 'score it alongthe As the formed .blank passes out from between the molding` drums, the individual units can be? read-ily broken apartrdue to the scoring, if

they have not been completely severed by the knife edges. Y Y

vWhat I claim is: Y 1. Y* In molding apparatus, a drum having a plurality of mold cavities in its periphery,

The knife edges on the drums are and a'removablel Aplate formingthe bottom mold and a layer of solid, inelastic cushion- -of each cavity and constituting apart oftl'ieV o ing material"substantially filling the spaces i between Athe said drum and each plate. l "2. In molding'app'aratus, a drum having a plurality of mold cavities inl its periphery,"a removable lplate forming the bottom of each and the drum.

cavity, and a cushion layerbetween 'said plate 3. In. molding apparatus, a. drum having mold cavities in its face, av steel plate lying in each cavityand forming the bottom ofthe mold, anda layer of av relatively'soft metal between eachplate'and the face Vof the drum'.

1. In molding apparatusLa drum compris-V ing a'cylinder having its vouter face subdivided 'into a'plurality of mold cavities, a plate mounted in each cavity and forming the bottomthereof, and means for securing .the

plate in position, theplate being curved'and of tapering thicknessV from end to end and a layer of Vinelastic metallic cushioning' materialbetween each ofsaidplates and the drum andadapted uniformly to support on the l drum the entire surface vof the platel 5. lIn molding apparatus, a drum having i its surface subdivided into a Aplurality of mold cavities, a removable'plate lying in each cavity and" forming the bottom thereof, this plate having a taperingv thickness from endto v end with itsthick end leading-in the direction i of movement in'which the drum is to bero'- tated,'and means for securing'the plate to the drum and a cushion of in'elasticsolid material between eachof the said plates and the drum.V i

6'. In a moldingapparatus, a drum havingy its surfaces subdivided into va plurality; of molding cavities, a removable plate lying in each cavity, said plates having theirupperk u surfaces shaped to conform to articles'to be molded, and a yieldable, inelastic cushion Ybetween eachrofv said plates `and said-drum.

' 7.' In a molding apparatus, a drum having its surface subdivided into a plurality of molding cavities, a removable plate lying in each cavity, said plates having their upper surfaces shaped to conform to articles to be s molded, and a yieldable cushion of a relatively soft inelastic metal between each of said plates and said drum.

8. A molding device comprising a hollow molding drum having a plurality of molding m cavities in the outer surface thereof and openings extending from said cavities to the inner surface thereof, a plate overlying the bottom of each cavity, bolts securing said plates to said drum, and a layer of lead be- 15 tween each plate and the drum and filling said openings. t

9. A molding device comprising a molding drum having molding cavities therein and openings extending from the bottoms of said 2o cavities, plates overlying the bottoms of said cavities, means for securing the plates in place, and a cushion of soft inelastic metal between said plates and drum.

10. In molding apparatus for producing roofing elements and the like, a `drum having a plurality of mold cavities in its periphery, a removable plate forming the bottom of each cavity and constituting a part of the mold, a knife edge defining each cavity, and a layer :ic of solid cushioning material between the said plate and the drum.

1l. In molding apparatus for producing roofing elements and the like, a drum having circumferential knife edges on its outer Vsurx5 face, a plurality of axially-disposed knife edges on the drum surface disposed between adjacent circumferential knife edges and out of alignment With those axially-disposed knife edges on the opposite side of each of m the adjacent circumferential knife edges, the respective knife edges forming a plurality of mold cavities in the drum periphery, an adjustable removable plate forming the bottom of each cavity, and a cushioning layer of solid 45 material separating the said plate and the drum.

12. In molding apparatus for producing roofing elements and the like, a drum having a plurality of circumferential knife edges on its outer face, a row of knife edges lying between adjacent circumferential knife edges and disposed at an angle thereto, a plate secured to the face of the drum and lying in the space defined by a pair of contiguous cir- *5 cumferential knife edges and by a pair of contiguous knife edges arranged at an angle thereto, and a cushion of inelastic yieldable material between the said plate and the drum. In testimony whereof I aix my signature.

6 THOMAS ROBINSON. 

